The way I see the similarities in both have more to do with the 2d pixel vs 3d polygon era.
FFVII was the first FF to use 3d graphics. The signficance of this was a sense of realism which you didn't previously have in RPGs. If anyone played the previous ones, including FFVI, during battles the player/ enemy "attacks" with an animation, but they don't actually physically strike them as they do in FFVII. That was the sense of realism you got from 3d battles, not to mention the CGI cutscenes for the first time ever, despite the fact the backgrounds we still static images. (and well done at that). This was the PSX and the start of the 3d era which was then heavily flooding the gaming market (lest we forget the 3do).
SOTN was the last Consolevania to use 2d pixel style graphics (interestingly while running on a 3d engine.) It was also the first exploration based CV and perhaps gave more of a sense of realism and scale to 'Castlevania', rather than the castle being part of the game, or being played through in segments. Also the first CV to feature voice actors. This was the end of the 2D era so to speak, most games were now converging into their 3d counterparts.
Both mark the start/ end of an era in gaming.